<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta http-equiv="X-UA-Compatible" content="IE=edge" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <link rel="stylesheet" href="./css/inputnumber.css" />
  <link rel="stylesheet" href="./css/index.css" />
  <title>购物车</title>
</head>

<body>
  <div class="app-container" id="app">
    <!-- 顶部banner -->
    <div class="banner-box"><img src="http://autumnfish.cn/static/fruit.jpg" alt="" /></div>
    <!-- 面包屑 -->
    <div class="breadcrumb">
      <span>🏠</span>
      /
      <span>购物车</span>
    </div>
    <!-- 购物车主体 -->
    <div class="main">
      <div class="table">
        <!-- 头部 -->
        <div class="thead">
          <div class="tr">
            <div class="th">选中</div>
            <div class="th th-pic">图片</div>
            <div class="th">单价</div>
            <div class="th num-th">个数</div>
            <div class="th">小计</div>
            <div class="th">操作</div>
          </div>
        </div>
        <!-- 身体 -->
        <div class="tbody">

          <!-- 渲染需要的行 -->
          <!-- 
            <div class="tr">
            <div class="td"><input type="checkbox" checked /></div>
            <div class="td"><img src="http://autumnfish.cn/static/火龙果.png" alt="" /></div>
            <div class="td">6</div>
            <div class="td">
              <div class="my-input-number">
                <button class="decrease"> - </button>
                <span class="my-input__inner">2</span>
                <button class="increase"> + </button>
              </div>
            </div>
            <div class="td">12</div>
            <div class="td"><button class="del">删除</button></div>
          </div> 
        -->

        </div>
      </div>
      <!-- 底部 -->
      <div class="bottom">
        <!-- 全选 -->
        <label class="check-all">
          <input type="checkbox" />
          全选
        </label>
        <div class="right-box">
          <!-- 所有商品总价 -->
          <span class="price-box">总价&nbsp;&nbsp;:&nbsp;&nbsp;¥&nbsp;<span class="price">24</span></span>
          <!-- 结算按钮 -->
          <button class="pay">结算( 6 )</button>
        </div>
      </div>
    </div>
    <!-- 空车 -->
    <div class="empty">🛒空空如也</div>
  </div>
  <script>
    const dataArr = [
      {
        id: 1,
        icon: 'http://autumnfish.cn/static/火龙果.png',
        isChecked: true,
        num: 2,
        price: 6,
      },
      {
        id: 2,
        icon: 'http://autumnfish.cn/static/荔枝.png',
        isChecked: false,
        num: 7,
        price: 20,
      },
      {
        id: 3,
        icon: 'http://autumnfish.cn/static/榴莲.png',
        isChecked: false,
        num: 3,
        price: 40,
      },
      {
        id: 4,
        icon: 'http://autumnfish.cn/static/鸭梨.png',
        isChecked: true,
        num: 10,
        price: 3,
      },
      {
        id: 5,
        icon: 'http://autumnfish.cn/static/樱桃.png',
        isChecked: false,
        num: 20,
        price: 34,
      },
    ]
    const tbody = document.querySelector('.tbody')
    const sum = document.querySelector('.price-box .price')
    const checkAll = document.querySelector('.check-all input')
    function render(){
      const res = dataArr.map((item,index) =>{
        return `<div class="tr" data-index="${index}">
            <div class="td"><input type="checkbox" ${ item.isChecked ? 'checked' : '' } /></div>
            <div class="td"><img src="${item.icon}" alt="" /></div>
            <div class="td">${item.price}</div>
            <div class="td">
                <div class="my-input-number">
                  <button class="decrease"> - </button>
                  <span class="my-input">${item.num}</span>
                  <button class="increase"> + </button>
                </div>
            </div>
            <div class="td">${item.num * item.price}</div>
            <div class="td"><button class="button del">删除</button></div>
          </div> `})
          tbody.innerHTML = res.join('')
          
          //全选按钮 + 总价：先判断所有的小按钮是否都选中，筛选已选中的按钮，把小计相加
          checkAll.checked = dataArr.every(item => item.isChecked)
          const newArr = dataArr.filter(item => item.isChecked)
          //计算总价格
          const totalPrice = newArr.reduce((prev,item) => prev + item.num * item.price,0 )
          sum.innerHTML = totalPrice.toFixed(2)
          //计算结算中括号的总数量
          const totalNum = newArr.reduce((prev,item) => prev + item.num,0)
          document.querySelector('.pay').innerHTML = `结算( ${totalNum} )`
          // 空空如也
          const empty = document.querySelector('.empty')
          dataArr.length === 0 ? empty.style.display = 'block' : empty.style.display = 'none' 
    }
    render()
    //删除模块
    tbody.addEventListener('click',function(e){
      //删除按钮
      if(e.target.className === 'button del'){
        dataArr.splice(e.target.dataset.index,1)
        render()
      }
      //增加数量模块
      if(e.target.className === 'increase'){
        const index = e.target.parentNode.parentNode.parentNode.dataset.index
        dataArr[index].num++
        render()
      }
      //减少数量模块
      if(e.target.className === 'decrease'){
        const index = e.target.parentNode.parentNode.parentNode.dataset.index
        if(dataArr[index].num > 1){
          dataArr[index].num--
        }else{
          dataArr[index].num = 1
        } 
        render()
      }
      // 小复选框业务是否全选开控制总的复选框
      if (e.target.tagName === 'INPUT') {
        const index = e.target.parentNode.parentNode.dataset.index
        dataArr[index].isChecked = e.target.checked
        render()
      }
    })
    // 添加全选按钮的点击事件
    checkAll.addEventListener('change', function () {
      dataArr.forEach(item => item.isChecked = this.checked)
      render()
    })
    
  </script>
</body>

</html>